With the Doctor cornered in the underground caves by androids, Adric ventures outside of the TARDIS and manages to destroy one of them. They get control of the situation and the Doctor manages to open the door they've located - but in doing so, he's activated a bomb. They set off to find who is behind it all and arrive on board a spaceship on its way to Earth. Unknown to them as yet is that it's all down to the Cybermen, who are determined to destroy the Earth. Written by
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You can tell that most of the shots of outer space are still pictures. See more
[regarding the inside of the TARDIS
It's bigger than you think.